v1.0.59: pause/resume sync

New PAUSED status. When a sync is running, the sync button becomes a
pause button (⏸). Tapping it cancels the WorkManager job and sets the
status to PAUSED (purple). The button then becomes a play button (▶) to
resume. Works in both the home screen card and the pair detail screen.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/src/main/kotlin/com/syncflow/domain/model/SyncPair.kt

@@ -70,5 +70,5 @@ enum class ScheduleType(val label: String) {
 }
 
 enum class SyncStatus {
-    IDLE, SYNCING, SUCCESS, PARTIAL, FAILED, CONFLICT,
+    IDLE, SYNCING, PAUSED, SUCCESS, PARTIAL, FAILED, CONFLICT,
 }